A dual news conference Friday designed to reinforce the historic Super Bowl narrative of opposing coaches as brothers only further revealed the vast yet unspoken differences between them. Born only 15 months apart, yet seemingly from different centuries, the only things the Harbaughs seemingly share are a last name and a jawline. Listen to them speak, watch them work, talk to the people around them, and a complicated dynamic can be illustrated in one simple, if harsh, perception.

It's easy to cheer for John. It's almost impossible to cheer for Jim.

John, playing the part of the wise older brother with grace, is engaging and likable. Jim, playing the annoying younger brother down to the last grimace, is terse and distant.

Both men, ages 50 and 49, have the undying devotion of their players, as reflected in two teams that consistently play hard and smart. Both men are considered outstanding strategists unafraid to make bold decisions, witness the middle of this season when John was changing offensive coordinators as Jim was changing quarterbacks.

But the similarities end, quite literally, as soon as the game ends. John is known for some of the league's longest postgame handshakes or hugs with opposing coaches. Jim is known as the only coach who can turn that handshake into a fight; just ask Jim Schwartz or Pete Carroll.

John says all the right things, gets all the right jokes, makes all the right moves, whether it be setting up a news conference so the most veteran reporter in the room asks the first question or playfully imitating his brother's cliches.

Jim is the opposite of charming, visibly bristling at his surroundings, looking strangely at reporters, refusing this week to answer a query about his favorite food, snapping at the poor journalist who referred to the string hanging around his neck during games as a "necklace."

"I take great offense that you call it a necklace," he said. "It's a whistle."

Perhaps fittingly, a difference between the brothers was epitomized Friday when they were asked about their "philosophical commonalities."

Jim said, "I would be hard-pressed to spell philosophical right now."

John then pleasantly and thoughtfully answered the question.

Those in the 49ers camp say one can know Jim for years, yet when walking past him in the hallway he might act as if he's never seen them before. Those in the Ravens camp marvel about how John never forgets anybody. He proved that this week when he answered a question from a Philadelphia reporter by first detailing the reporter's odd wardrobe when the guy covered the Eagles and John was an assistant coach.

Jim's most memorable quote this season was an odd and awkward rip of reporters who had questioned his handling of Alex Smith, saying, "I think it's just a lot of gobble gobble turkey . . . just gobble gobble turkey from jive turkey gobblers." John, meanwhile, answered a simple question about his feelings for New Orleans by detailing and complimenting the food that was cooked for the team by receiver Jacoby Jones' mother.

Jim's tight and close demeanor is mirrored by his players, who are guarded with the media and workmanlike on the field. John's open arms also are reflected in his players, who are Ray Lewis loud and Joe Flacco proud.

"We'll play with character, we'll play with class," John said.

While there have been many stories detailing the competitive conflicts between the two men when they were children — "Playing any sport with Jim growing up was a test of will for all of us," John said — the differences in their approaches were perhaps honed in adulthood.

John was a nondescript defensive back at Miami of Ohio before beginning a coaching journey in which he was an assistant at five colleges before serving as the Eagles' special-teams coach for nine long years and as defensive backs coach for another. He was so anonymous, when UCLA considered him as a possible replacement for Karl Dorrell in 2007, most fans in L.A. had never even heard of him.

Jim traveled his path under a far more starry sky. He was a famous quarterback at Michigan, he had a 14-year career as a quarterback in the NFL, and he was an assistant for only one college and one NFL team before becoming a college head coach and winding up in the NFL seven years later.

One can imagine John feeling like it took him a lifetime to reach this head-coaching moment while Jim just sort of floated in on gifted wings. This is certainly how they act, with John clearly appreciative of every moment this week while Jim acts as if the Super Bowl is a combination of traffic jam and toothache.

When the news conference ended Friday with a family photo that included the Harbaughs' parents and a grandparent, John greeted everyone on the stage, directed them where to stand, and ended it by giving his mother a warm embrace that seemed to last for hours.

Jim, meanwhile, stood to the side, jumped in the photo at the last minute, and then gave his mother a quick peck before disappearing.

Come Sunday, only one of them will win. But in reality, one of them already has.